Five Aside: Group winners reign

The Round of 16 ended with the final two group winners advancing to the quarterfinals, marking the first time that all eight have done so in a single World Cup. Belgium reaches the quarterfinals for the second time ever and first time since 1986 with its 2-1 extra-time win over the United States in Salvador. It was the first time that the U.S. had reached consecutive knockout stages in the World Cup. The U.S. has not reached the quarterfinals since 2002.

In São Paulo, Argentina reached its third straight World Cup quarterfinals for the first time with a 1-0 extra-time win over Switzerland, joining Germany and Brazil as the only teams to make it that far in each of the last three tournaments. Switzerland was shut out in its third straight World Cup knockout round game with the result, last scoring a goal at this stage of a World Cup in 1954, which is also the last time the Swiss were in the quarterfinals.

Here are five story lines from the final day of this year's Round of 16.

With three goals in extra time in the Belgium-United States game, the drama continues to come late at this World Cup. It was the fifth Round of 16 game at this tournament to go into extra time, the most ever in a single Round of 16, and this year's particularly specialized in late goals. With five in the extra-time period at this tournament, the most in the Round of 16 in World Cup history, 67 percent of the goals in the knockout round were scored after the 75th minute.

Clint Dempsey and the U.S. came up just shy against Belgium.

Tim Howard did what he could to keep the Americans in the game against Belgium, which took 38 shots, the most taken by any team in a game at this World Cup. The U.S.' all-time leader in appearances for a goalkeeper finished the game with 16 saves, the most in a World Cup game over the last 50 years. Howard finished the tournament with 28 total saves, five more than Algeria's Rais M'bolhi for the tournament lead.

At 19 years and 25 days, Julian Green became the youngest player to ever appear in a World Cup for the United States when he was subbed on for Alejandro Bedoya in the 105th minute. His goal two minutes later to decrease Belgium's lead to one made him the youngest American goal scorer in World Cup history and the youngest World Cup goal scorer since Lionel Messi in 2006.

With Argentina's win, the five teams with the highest pre-World Cup chance of making the quarterfinals, according to Soccer Power Index projections, have all advanced. Spain was the team with the best chance to make the quarters that did not get there (45 percent), while Costa Rica has made it to the final eight despite being the 26th-most likely (or seventh-least likely) to make it there when the tournament kicked off (10 percent).

Blerim Dzemaili was inches away from equalising for Switzerland against Argentina deep into extra time.

Ángel Di María picked the perfect time to score his first World Cup goal. His 118th-minute strike was the one of the latest game-winners in World Cup history, with David Platt's 120th-minute goal for England against Belgium in 1990 the latest. Di María's 12 shots against Switzerland were the most in a World Cup game since Italy's Luigi Riva took 13 in 1970. Lionel Messi was also productive throughout the game, creating eight scoring chances, the most by a player in a game at this World Cup.